ENGINE AR-CORE 3505501 - Caterpillar

Illustration 3 g02263393The values in Table 3 are for bench testing only. Values may not represent parameters for machine systems specifications.
Table 3
Operating pressure 10 MPa
Supply Voltage +7V ~ +14V
Output signal 500 100 Hz (PWM)
Output range 5% ~ 95% The low-pressure sensors include:
Negative Flow Control 1 Pressure Sensor
Negative Flow Control 2 Pressure SensorNegative Flow Control Pressure Sensors
The negative flow control pressure sensors for the drive pump and idler pump are inputs to the machine ECU. The machine ECU uses this pressure information to determine the hydraulic demand requested by the operator. The machine ECU then sends a PWM driver to the power shift solenoid to control the pump flow rate.The NFC pressure sensors are located on the top on the main control valve in the end plate. For more information on the NFC pressure sensors, refer to Systems Operation, "Negative Flow Control System".High Pressure Sensors
Illustration 4 g02263513The values in Table 4 are for bench testing only. Values may not represent parameters for machine systems specifications.
Table 4
Operating Pressure 50 MPa
Supply Voltage +7V ~ +14V
Output Signal 500 100 Hz (PWM)
Output Range 5% ~ 95% The high-pressure sensors include:
Pump 1 Pressure Sensor (drive pump)
Pump 2 Pressure Sensor (idler pump)Drive Pump Pressure Sensor and Idler Pump Pressure Sensor
The drive pump pressure sensor and idler pump pressure sensors are inputs to the machine ECU. The drive pump and idler pump pressure sensors are located on the main control valve. The drive pump pressure sensor monitors the pressure of the drive pump oil in the left half of the main control valve high-pressure passages. The idler pump pressure sensor monitors the idler pump oil pressure in the right half of the main control valve high-pressure passages. The pressure sensors send a pulse width modulated (PWM) input to the machine ECU. This pressure information is used for pump control and travel speed.Outputs
The ECU responds to decisions by sending electrical signals to the outputs. The outputs can create an action or the outputs can provide information to the operator or the service technician.Proportional Reducing Solenoid Valve
Illustration 5 g03462498The values in Table 5 are for bench testing only. Values may not represent parameters for machine systems specifications.
Table 5
Current Range 0 mA ~ 700 mA
Coil Resistance 11.5 0.5Ω (T=20° C)
Illustration 6 g03462556
A - Port pressure (kPa) vs Current (mA)
The P-Port is blocked and does not allow pressure to the A-port. Therefore, the machine ECU must apply current to the PRV in order to sent pressure to the A-port of the PRV.The PRV's include:
Negative Flow Control 1 Limit PRV
Negative Flow Control 2 Limit PRV
Power Shift Pressure PRVNegative Flow Control 1 Limit PRV and Negative Flow Control 2 Limit PRV
Two proportional reducing valves for negative flow control are used to control the amount of NFC signal to the pump regulators. The machine ECU receives various input signals to control the flow limitation from the main hydraulic pumps. When the NFC valves are energized by the machine ECU, pilot oil pressure is directed to the main hydraulic pump regulators from the pilot manifold.